Surgical stapling device with articulation lock assembly

ABSTRACT

A surgical stapling device includes a body portion that defines a longitudinal axis and a tool assembly that articulates about an axis transverse to the longitudinal axis. An articulation link assembly is supported in the body portion and is movable between retracted and advanced positions to pivot the tool assembly between a non-articulated position and articulated positions. The articulation assembly supports an articulation lock assembly that is movable from a locked position to an unlocked position in response to longitudinal movement of the articulation assembly to facilitate articulation of the tool assembly. The articulation lock assembly stabilize the articulation link assembly within the body portion when the surgical stapling device is fired to minimize occurrence of tremors in the tool assembly.

FIELD

This disclosure is directed to surgical stapling devices and, more particularly, to surgical stapling devices that have articulating tool assemblies.

BACKGROUND

Surgical stapling devices for suturing and cutting tissue in a fast and efficient manner to perform a variety of surgical procedures are well known. Typically, a surgical stapling device includes a tool assembly that has first and second jaws that support a cartridge assembly and an anvil, respectively. The first and second jaws are mounted together to allow for movement of the tool assembly between open and clamped positions.

Typically, endoscopic surgical stapling devices include an elongate shaft that defines a longitudinal axis and the tool assembly is pivotably supported on a distal end of the elongate shaft about a pivot member that defines a transverse axis. In known endoscopic stapling devices, an articulation rod is coupled to the tool assembly and is movable between retracted and advanced positions to pivot the tool assembly about the transverse axis between a non-articulated position and articulated positions. When the position of the tool assembly is moved to a desired articulated position and the tool assembly is clamped and fired, due to the inherent clearances of the components in the reload assembly and the firing forces required to fire the stapling device, the articulation rod may undesirably experience tremors that are transferred to the tool assembly.

Accordingly, a continuing need exists in the suturing arts for a surgical stapling device that can minimize tremors during firing of the stapling device.

SUMMARY

This disclosure is directed to surgical stapling device that includes a body portion that defines a longitudinal axis and a tool assembly that articulates about an axis transverse to the longitudinal axis. The surgical stapling device includes an articulation link assembly that is supported in the body portion and is movable between retracted and advanced positions to pivot the tool assembly between a non-articulated position and articulated positions. The articulation assembly supports an articulation lock assembly that is movable from a locked position to an unlocked position in response to longitudinal movement of the articulation assembly to facilitate articulation of the tool assembly. The articulation lock assembly stabilizes the articulation link assembly within the body portion when the surgical stapling device is fired to minimize occurrence of tremors in the tool assembly.

Aspects of this disclosure are directed to a surgical stapling device including an elongate body, an articulation mechanism, and an articulation lock assembly. The elongate body has a distal portion and a proximal portion and defines a longitudinal axis. The tool assembly is pivotably secured to the distal portion of the elongate body about a pivot axis that is perpendicular to the longitudinal axis. The tool assembly is movable between a non-articulated position and articulated positions. The articulation mechanism includes a first articulation link assembly that includes a first proximal articulation link and a first distal articulation link. The first distal articulation link is pivotably coupled to the tool assembly. The first proximal articulation link is movable between retracted and advanced positions through a first intermediate position to move first distal articulation link between retracted and advanced positions to move the tool assembly between a non-articulated position and articulated positions. The articulation lock assembly includes a lock member that is secured to the first distal articulation link and is movable between locked and unlocked positions in response to movement of the first proximal articulation link.

Other aspects of the disclosure are directed to an articulation mechanism that includes a first articulation link assembly and an articulation lock assembly. The first articulation link assembly includes a first proximal articulation link and a first distal articulation link. The first proximal articulation link is movable between retracted and advanced positions through a first intermediate position to move the first distal articulation between advanced and retracted positions. The articulation lock assembly includes a lock member that is secured to the first distal articulation link and is movable between locked and unlocked positions in response to movement of the first proximal articulation link. The first proximal articulation link is coupled to the first distal articulation link to facilitate relative movement between the first proximal articulation link and the first distal articulation link as the lock member is moved between the locked and unlocked positions.

Other aspects of the disclosure are directed to a surgical stapling device that includes a tool assembly, an articulation mechanism, and an articulation lock assembly. The elongate body has a distal portion and a proximal portion and defines a longitudinal axis. The tool assembly is pivotably secured to the distal portion of the elongate body about a pivot axis that is perpendicular to the longitudinal axis. The tool assembly is movable between a non-articulated position and articulated positions. The articulation mechanism includes first and second articulation link assemblies. The first articulation link assembly includes a first proximal articulation link and a first distal articulation link. The first distal articulation link is pivotably coupled to the tool assembly. The first proximal articulation link is movable between retracted and advanced positions through a first intermediate position to move the first distal articulation link between retracted and advanced positions to move the tool assembly between a non-articulated position and articulated positions. The second articulation link assembly includes a second proximal articulation link and a second distal articulation link. The second proximal articulation link is movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link and the second pivot link between retracted and advanced positions. The articulation lock assembly includes a lock member and a biasing member. The lock member is secured to the first distal articulation link and is movable between locked and unlocked positions in response to movement of the first proximal articulation link.

In aspects of the disclosure, the lock member is pivotably supported on the first distal articulation link.

In some aspects of the disclosure, the articulation lock assembly includes a biasing member that urges the lock member towards the locked position.

In certain aspects of the disclosure, the biasing member includes a coil spring.

In aspects of the disclosure, the first distal articulation link defines a cavity and the lock member is pivotably supported within the cavity.

In some aspects of the disclosure, the first proximal articulation link has an engagement member that is received within the cavity and is movable into engagement with the lock member to move the lock member from the locked position to the unlocked position.

In certain aspects of the disclosure, the lock member defines distal and proximal ramp surfaces and the engagement member includes an abutment member.

In aspects of the disclosure, the abutment member is positioned between the distal and proximal ramp surfaces when the first proximal articulation link is in the first intermediate position and is movable into engagement with one of the distal and proximal ramp surfaces to move the lock member from the locked position to the unlocked position.

In some aspects of the disclosure, the engagement member of the first proximal articulation link is coupled to the first distal articulation link to facilitate movement of the first proximal articulation link independently of the first distal articulation link as the lock member is moved between the locked position and the unlocked position.

In certain aspects of the disclosure, a toothed rack is supported within the elongate body and the lock member includes a protrusion that is engaged with the toothed rack when the lock member is in the locked position.

In aspects of the disclosure, the first articulation link assembly includes a pivot link that has a proximal portion that is pivotably coupled to the first distal articulation link and a distal portion that is pivotably coupled to one side of the tool assembly.

In some aspects of the disclosure, the articulation mechanism further includes a second articulation link assembly that includes a second proximal articulation link, a second distal articulation link, and a second pivot link.

In certain aspects of the disclosure, the second proximal articulation link is movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link and the second pivot link between retracted and advanced positions.

In aspects of the disclosure, the second proximal articulation link is coupled to the second distal articulation link to facilitate independent movement of the second proximal articulation link in relation to the second distal articulation link as the lock member moves between the locked and unlocked positions.

In aspects of the disclosure, the articulation mechanism includes a second articulation link assembly including a second proximal articulation link and a second distal articulation link, the second proximal articulation link movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link between retracted and advanced positions, the second proximal articulation link coupled to the second distal articulation link to facilitate relative movement between the second proximal articulation link and the second distal articulation link as the lock member is moved between the locked and unlocked positions.

Other aspects of the disclosure will be appreciated from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the disclosure are described herein below with reference to the drawings, wherein:

FIG. 1 is a side perspective view of a surgical stapling device according to aspects of the disclosure with a tool assembly of the stapling device in an open position;

FIG. 2 is a side perspective view of a distal portion of the surgical stapling device shown in FIG. 1 with the tool assembly in the open position and shown in phantom and an outer tube of an elongate body of the surgical stapling device removed;

FIG. 3 is an exploded view of a distal body portion of the surgical stapling device shown in FIG. 1 ;

FIG. 4 is an enlarged view of the indicated area of detail shown in FIG. 2 ;

FIG. 5 is a top perspective view of a lock member of an articulation lock assembly of the surgical stapling device shown in FIG. 1 ;

FIG. 6 is a bottom perspective view of a lock member of an articulation lock assembly of the surgical stapling device shown in FIG. 1 ;

FIG. 7 is a side perspective view of the distal portion of the surgical stapling device shown in FIG. 1 with the tool assembly in a clamped, non-articulated position with the outer tube of the elongate body of the surgical stapling device removed and the articulation lock assembly in a locked position;

FIG. 8 is an enlarged view of the indicated area of detail shown in FIG. 7 ;

FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 3 ;

FIG. 10 is an enlarged view of the indicated area of detail shown in FIG. 9 ;

FIG. 11 is a cross-sectional view taken along section line 11-11 of FIG. 3 ;

FIG. 12 is a cross-sectional view taken through the articulation lock assembly as the tool assembly is being articulated in a first direction with the articulation lock assembly in a locked position;

FIG. 12A is a cross-sectional view taken through the first proximal and distal articulation links as the lock member is moved to the unlocked position;

FIG. 13 is a top view the distal portion of the surgical stapling device with the tool assembly in an articulated position;

FIG. 14 is a side cross-sectional view taken through the articulation lock assembly with the articulation lock assembly in the locked position;

FIG. 15 is a cross-sectional view taken through the articulation lock assembly as the second tool assembly is being articulated in a second direction with the articulation lock assembly in an unlocked position;

FIG. 16 is a cross-sectional view taken through the articulation lock assembly with the articulation lock assembly in the locked position;

FIG. 17 is a side perspective, cutaway view of the distal portion of the surgical stapling device shown in FIG. 1 with an alternative version of the articulation lock assembly in the locked position;

FIG. 18 is a side perspective view of an articulation link and articulation lock assembly of the distal portion of the surgical stapling device shown in FIG. 17 ;

FIG. 19 is a side perspective cutaway view of the distal portion of the surgical stapling device shown in FIG. 17 with the articulation lock assembly shown in the locked position;

FIG. 20 is a side perspective cutaway view of the distal portion of the surgical stapling device shown in FIG. 19 with the articulation lock assembly shown in the unlocked position;

FIG. 21 is a side perspective cutaway view of the distal portion of the surgical stapling device shown in FIG. 19 with the articulation lock assembly shown in the locked position as the tool assembly is articulated in a first direction

FIG. 22 is a side perspective cutaway view of the distal portion of the surgical stapling device shown in FIG. 19 with the articulation lock assembly shown in the locked position as the tool assembly is articulated in a second direction;

FIG. 23 is a side perspective, cutaway view of the distal portion of the surgical stapling device shown in FIG. 1 with another alternative version of the articulation lock assembly in the locked position;

FIG. 24 is a side perspective view of articulation links and articulation lock assembly of the distal portion of the surgical stapling device shown in FIG. 23 ;

FIG. 25 is a bottom perspective view of an alternate version of the lock member of the articulation lock assembly of the surgical stapling device shown in FIG. 1 ;

FIG. 26 is a side perspective view of an alternate version of the second proximal articulation link of the articulation lock assembly of the surgical stapling device shown in FIG. 1 ;

FIG. 27 is a cross-sectional view taken along section line 27-27 of FIG. 23 illustrating an alternate version of the articulation lock assembly including the lock member shown in FIG. 25 and the second proximal articulation link shown in FIG. 26 ;

FIG. 28 is a cross-sectional view taken through the articulation lock assembly shown in FIG. 27 in a locked position; and

FIG. 29 is a cross-sectional view taken through the articulation lock assembly shown in FIG. 27 in an unlocked position.

DETAILED DESCRIPTION

The disclosed surgical stapling device will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the disclosed aspects are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure.

In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, the term “endoscopic” is used generally used to refer to endoscopic, laparoscopic, arthroscopic, and/or any other procedures conducted through a small diameter incision or cannula. Further, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel. Moreover, directional terms such as front, rear, upper, lower, top, bottom, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

The disclosed surgical stapling device includes a body portion defining a longitudinal axis, a tool assembly, an articulation mechanism, and an articulation lock assembly. The tool assembly is pivotably supported on the body portion and articulates about an axis transverse to the longitudinal axis. The articulation mechanism is supported within the body portion and is movable between retracted and advanced positions to pivot the tool assembly between a non-articulated position and articulated positions. The articulation lock assembly includes a lock member that is movable between unlocked and locked positions to stabilize the articulation mechanism when the surgical stapling device is fired to minimize occurrence of tremors in the tool assembly.

FIG. 1 illustrates a surgical stapling device shown generally as stapling device 10 that includes a handle assembly 12, an elongate body or adapter assembly 14, and a tool assembly 16. As illustrated, the handle assembly 12 is powered and includes a stationary handgrip 18 and actuation buttons 20. The actuation buttons 20 are operable to actuate various functions of the tool assembly 16 via the adapter assembly 14 including approximation, stapling, and cutting. In certain aspects of the disclosure, the handle assembly 12 supports batteries (not shown) that provide power to the handle assembly 12 to operate the stapling device 10. Although the stapling device 10 is illustrated as a powered stapling device, it is envisioned that aspects of this disclosure are suitable for use with manually powered surgical stapling devices as well as robotically controlled stapling devices.

The adapter assembly 14 defines a longitudinal axis “X” and includes a proximal portion 14 a that is coupled to the handle assembly 12 and a distal portion 14 b that supports the tool assembly 16. In aspects of the disclosure, the tool assembly 16 forms part of a reload assembly (not shown) that is removably supported on the distal portion 14 b of the adapter assembly 14 and can be replaced after the stapling device 10 is fired to facilitate reuse of the stapling device 10. The reload assembly can include the tool assembly 16 and a proximal body portion (not shown) that is coaxial with the adapter assembly 14 and is releasably coupled to the distal portion 14 b of the adapter assembly 14.

FIG. 2 illustrates a distal portion of the stapling device 10 including the tool assembly 16 shown in phantom and a mounting assembly 24. The tool assembly 16 defines a longitudinal axis “T” (FIG. 13 ) and includes a cartridge assembly 26 and an anvil assembly 28 that is coupled to the cartridge assembly 26 such that the tool assembly 16 is movable between the open (FIG. 2 ) and clamped positions (FIG. 7 ). In certain aspects of the disclosure, the cartridge assembly 26 is pivotably coupled to the anvil assembly 28 about a pivot axis “Y” and the tool assembly 16 is pivotable between the open and clamped positions. It is envisioned that the anvil assembly 28 could be pivotably coupled to the cartridge assembly 26. The mounting assembly 24 is fixedly coupled to the tool assembly 16 and is pivotably coupled to the distal portion 14 b (FIG. 1 ) of the adapter assembly 14 about a pivot axis “Z” to pivot the tool assembly 16 between a non-articulated position (FIG. 1 ) in which the longitudinal axis “T” of the tool assembly is coaxial with the longitudinal axis “X” of the adapter assembly 14 and articulated positions (e.g., FIG. 13 ) in which the longitudinal axis “T” of the tool assembly 16 defines an angle 1 with the longitudinal axis “X” of the adapter assembly 14. In aspects of the disclosure, the tool assembly is pivotable about the pivot axis “X” over an arc of about 180 degrees, wherein the angle 1 can be up to about 90 degrees on each side of the longitudinal axis “X” of the adapter assembly 14.

FIG. 3 illustrates the mounting assembly 24 of the stapling device 10 which includes an upper mounting member 30 and a lower mounting member 32. The upper and lower mounting members 30 and 32 are fixedly secured together with pins 34 and include a distal portion that is secured to the tool assembly 16 and a proximal portion that is pivotably coupled to the distal portion 14 b of the adapter assembly 14. The distal portion of each of the upper and lower and lower mounting members 30 and 32 includes a pivot member 36 (only one is shown) that are axially aligned and define the pivot axis “Z” (FIG. 2 ). The pivot members 36 are pivotably coupled to the distal portion 14 b of the adapter assembly 14 to pivotably couple the tool assembly 16 to the adapter assembly 14 about the pivot axis “Z”.

FIGS. 2 and 3 illustrate an articulation mechanism of the adapter assembly 14 which includes first and second articulation link assemblies 38 and 39 that extend along axes that are parallel to the longitudinal axis “X” (FIG. 1 ) of the adapter assembly 14. The first and second articulation link assemblies 38 and 39 are positioned on opposite sides of the adapter assembly 14 (FIG. 1 ) and include first and second proximal articulation links 40 and 42, respectively, first and second distal articulation links 44 and 46, respectively, and first and second pivot links 48 and 50, respectively. The first proximal articulation link 40 has a proximal portion 40 b and a distal portion 40 a. The proximal portion 40 b is coupled to an articulation drive member (not shown) that is positioned within the adapter assembly 14. U.S. application Ser. No. 16/809,829 discloses an articulation drive member that is suitable for use with the disclosed surgical stapling device 10. The articulation drive member (not shown) is actuable via the handle assembly 12 to affect longitudinal movement of the first proximal articulation link 40 within the adapter assembly 14. The first distal articulation link 44 has a proximal portion 44 b that is engaged with the distal portion 40 a of the first proximal articulation link 40 such that longitudinal movement of the first proximal articulation link 40 causes longitudinal movement of the first distal articulation link 44. In aspects of the disclosure, the first proximal articulation link 40 defines cutout 45 and the proximal portion 44 b of first distal articulation link 44 is received within the cutout 45 to facilitate relative movement between the first proximal articulation link 40 and the first distal articulation link 44. More specifically, distal movement of the first proximal articulation link 40 will not cause distal movement of the first distal articulation link 44 until a distal abutment surface 45 a of the first proximal articulation link 40 engages a proximal surface 44 c of the first distal articulation link 44. Similarly, proximal movement of the first distal articulation link 44 will not cause proximal movement of the first proximal articulation link 40 until the proximal surface 44 c of the first distal articulation link 44 bottoms out within the cutout 45 of the first proximal articulation link 40 and engages the distal abutment surface 45 a of the first proximal articulation link 40.

The first distal articulation link 44 includes a distal portion 44 a that is pivotably coupled to a proximal portion 48 b of the first pivot link 48 by a pivot pin 52. The first pivot link 48 has a distal portion 48 a that is pivotably coupled to one side of the mounting assembly 24 by one of the pins 34. The pins 34 define axes that are parallel to and laterally offset from the pivot axis “Z” (FIG. 2 ) such that distal movement of the first pivot link 48 causes the mounting assembly 24 and the tool assembly 16 about the pivot axis “Z” (FIG. 2 ) between a non-articulated position and non-articulated positions on a first side of the adapter assembly 14.

The second proximal articulation link 42 has a proximal portion 42 b and a distal portion 42 a. The proximal portion 42 b of the second proximal articulation link 42 is coupled to the articulation drive member (not shown) that is supported within the adapter assembly 14. The articulation drive member (not shown) is actuable via the handle assembly 12 (FIG. 1 ) to affect longitudinal movement of the second proximal articulation link 42 within the adapter assembly 14 (FIG. 1 ). The distal portion 42 a of the second proximal articulation link 42 includes an engagement member which may be in the form of an L-shaped extension 58. The engagement member 58 includes a downwardly extending abutment member 58 a as viewed in FIG. 3 . The second distal articulation link 46 includes a proximal portion 46 b that defines a cavity 60 (FIG. 3 ) and a channel 62 that extends through the proximal end of the second distal articulation link 46. The L-shaped extension 58 extends through the channel 62 such that the abutment member 58 a of the L-shaped extension 58 is received within the cavity 60. The configuration of the abutment member L-shaped extension 58 allows the second proximal articulation link 42 and the second distal articulation link 46 to move in relation to each other, but prevents passage of the abutment member 58 a through the channel 62 to prevent separation of the distal portion of the second proximal articulation link 42 from the proximal portion 46 b of the second distal articulation link 46. The second proximal articulation link 42 includes a distal surface 42 c (FIG. 3 ) that is movable into engagement with a proximal surface 46 c of the second distal articulation link 46. When the second proximal articulation link 42 is moved distally within the adapter assembly 14 (FIG. 1 ), the second proximal articulation link 42 will move independently of the second distal articulation link 46 until the distal surface 42 c of the second proximal articulation link 42 engages the proximal surface 46 c of the second distal articulation link 46. When the distal surface 42 c of the second proximal articulation link 42 engages the proximal surface 46 c of the second distal articulation link 46, distal movement of the second proximal articulation link 42 causes distal movement of the second distal articulation link 46 within the adapter assembly 14 (FIG. 1 ).

The second distal articulation link 46 includes a distal portion 46 a that is pivotably coupled to a proximal portion 50 b of the second pivot link 50 by a pivot pin 66. A distal portion 50 a of the second pivot link 50 is pivotably coupled to the other side of the mounting assembly 24 by one of the pins 34. As described above, the pins 34 define axes that are parallel to and laterally offset from the pivot axis “Z” (FIG. 2 ) such that distal movement of the second pivot link 50 causes the mounting assembly 24 and the tool assembly 16 about the pivot axis “Z” between a non-articulated position and non-articulated positions on a second side of the adapter assembly 14.

FIG. 3 illustrates a housing 70 (FIG. 4 ) of the adapter assembly 14 which includes a first half section 70 a and a second half-section 70 b. The first and second half-sections 70 a and 70 b are coupled together using pins, interlocking structure, and/or welding to define channels 72 through which the first and second articulation link assemblies 38 and 39 translate within the adapter assembly 14 (FIG. 1 ). The channels 72 confine the first and second articulation link assemblies 38 and 39 to longitudinal movement within the housing 70. The housing 70 supports a toothed rack 74 that includes a plurality of teeth 74 a.

FIGS. 3-6 illustrate an articulation lock assembly 80 of the stapling device 10 which includes a lock member 82 and a biasing member 84. The lock member 82 includes a body 86 that has a proximal portion and a distal portion. The proximal portion of the body 86 of the lock member 82 includes a transverse bore 88 (FIG. 3 ) that receives a pivot member 90. The pivot member 90 defines a vertical axis as viewed in FIG. 4 and is received within the transverse bore 88 of the lock member 82 and in bores 92 (FIG. 3 ) defined in the proximal portion 46 b of the second distal articulation link 46 to pivotably secure the lock member 82 within the cavity 60 of the second distal articulation link 46. The lock member 82 is pivotable within the cavity 60 of the second distal articulation link 46 between a locked position (FIG. 8 ) and an unlocked position (FIG. 12 ). In the locked position, the lock member 82 is engaged with the teeth 74 a (FIG. 3 ) of the toothed rack 74 to secure the second distal articulation link 46 in a fixed position as described in further detail below.

The distal portion of the body 86 of the lock member 82 includes a protrusion 96 and spaced distal and proximal cam surfaces or ramps 98 a and 98 b. The protrusion 96 may be in the form of a tooth that is received between adjacent teeth 74 a of the toothed rack 74 when the lock member 82 is moved to the locked position to inhibit longitudinal movement of the second distal articulation link 46 during firing of the stapling device 10. The distal ramp 98 a and the proximal ramp 98 b are axially aligned with the abutment member 58 a of the engagement member 58 in define a cavity 99 therebetween. When the lock member 82 of the articulation lock assembly 80 is in the locked position, the abutment member 58 a of the engagement member 58 of the second proximal articulation link 42 is positioned between the distal and proximal ramps 98 a and 98 b within the cavity 99. When the second proximal articulation link 42 is advanced or retracted within the adapter assembly 14 (FIG. 1 ), the abutment member 58 a will engage one of the distal and proximal ramps 98 a and 98 b, respectively, (depending on the direction of movement of the second proximal articulation link 42) to move the lock member 82 away from and out of engagement with the toothed rack 74 to the unlocked position. In aspects of the disclosure, the protrusion 96 and the spaced distal and proximal cam surfaces or ramps 98 a and 98 b extend inwardly from the lock member 82 towards the longitudinal axis “X” of the adapter assembly 14 (FIG. 1 ).

The biasing member 84 of the articulation lock assembly 80 is positioned to urge the protrusion 96 of the lock member 82 of the articulation lock assembly 80 towards the toothed rack 74 to the locked position. In aspects of the disclosure, the body 86 of the lock member 82 has an outwardly facing surface 100 (FIG. 5 ) that defines a blind bore 102 and the biasing member 84 is in the form of a coil spring 84 a (FIG. 4 ) that is received within the blind bore 102. The coil spring 84 a is compressed between an outer tubular body portion 104 (FIG. 1 ) of the adapter assembly 14 and the outwardly facing surface 100 of the lock member 82 to urge the lock member 82 inwardly towards the toothed rack 74 and the locked position. It is envisioned that the biasing member 84 may include a variety of different types of springs including torsion springs, leaf springs or the like. It is also envisioned that the biasing member 84 can positioned to engage the lock member 82 in variety of different manners.

FIGS. 7-11 illustrate the tool assembly 16 in a non-articulated position with the articulation lock assembly 80 in a locked position. In this position, the first and second proximal articulation links 40 and 42 are in an intermediate position between advanced and retracted positions. When the second proximal articulation link 42 is in its intermediate position, the abutment member 58 a of the L-shaped extension or engagement member 58 is positioned in the cavity 60 (FIG. 10 ) defined between the ramps 98 a and 98 b of the distal portion of the body 86 of the lock member 82 of the articulation lock assembly 80. When the abutment member 58 a is received in the cavity 60, the lock member 82 is urged by the biasing member 84 to the locked position in which the protrusion 96 of the lock member 80 is received between adjacent teeth 74 a of the rack 74 which is fixedly secured to the housing 70 of the adapter assembly 14 (FIG. 1 ). This locks the second distal articulation link 46 from longitudinal movement. In this position, a space “S1” (FIG. 10 ) is defined between the proximal surface 46 c (FIG. 8 ) of the second distal articulation link 46 and the distal surface 42 c of the second proximal articulation link 42. A space “S2” (FIG. 11 ) is also defined between the proximal surface 44 c of the first distal articulation link 44 and the distal abutment surface 45 a of the first proximal articulation link 40. These spaces “S1” and “S2” allow the lock member 82 to move from the locked position to the unlocked position prior to articulation of the tool assembly 16 as described below.

FIGS. 12-13 illustrate operation of the first and second articulation assemblies 38 (FIG. 12A) and 39 (FIG. 12 ) as the tool assembly 16 is articulated to a first side of the adapter assembly 14 in the direction indicated by arrow “A” in FIG. 13 . Although not shown or described in detail herein, the articulation drive member in the adapter assembly 14 (FIG. 1 ) is adapted to drive the first and second proximal articulation links 40 and 42, respectively, in equal and opposite directions. When the second proximal articulation link 42 is advanced in the direction of arrow “B” shown in FIG. 12 , the first proximal articulation link 40 is retracted in the direction of arrow “C” in FIG. 12A. As the second proximal articulation link 42 is advanced in the direction of arrow “B”, the second proximal articulation link 42 will move independently of the second distal articulation link 46 until the distal surface 42 c of the second proximal articulation link 42 engages the proximal surface 46 c (FIG. 12 ) of the second distal articulation link 46. When the distal surface 42 c of the second proximal articulation link 42 engages the proximal surface 46 c of the second distal articulation link 46, distal movement of the second proximal articulation link 42 will cause corresponding distal movement of the second distal articulation link 46 to advance the second pivot link 50 and articulate or pivot the tool assembly 16 about the pivot axis “Z” (FIG. 2 ).

Before the tool assembly 16 can be pivoted about the pivot axis “Z”, the articulation lock assembly 80 must be moved from the locked position (FIG. 10 ) to the unlocked position (FIG. 12 ). Movement of the articulation lock assembly 80 to the unlocked position occurs as the distal surface 42 c of the second proximal articulation link 42 moves towards the proximal surface 46 c of the second proximal articulation link 42 independently of the second distal articulation link 46. More specifically, as the second proximal articulation 42 moves in the direction of arrow “B” in FIG. 12 independently of the second distal articulation link 46, the abutment member 58 a of the engagement member 58 of the second proximal articulation link 42 moves within the cavity 60 defined in the proximal portion 46 a of the second distal articulation link 46 and engages the distal ramp 98 a of the lock member 82 to urge the lock member 82 of the articulation lock assembly 80 in the direction of arrow “D” in FIG. 12 from the locked position (FIG. 11 ) to the unlocked position (FIG. 12 ). In the unlocked position, the protrusion 96 of the lock member 82 is moved from between adjacent teeth 74 a of the rack 74 to a position spaced from the rack 74.

FIG. 12A illustrates the position of the first proximal articulation link 40 and the first distal articulation link 44 at the point in which the lock member 82 of the articulation lock assembly 80 is moved to the unlocked position but prior to articulation of the tool assembly 16 (FIG. 13 ). As described above, the articulation drive member (not shown) of the adapter assembly 14 (FIG. 1 ) is coupled to the first proximal articulation link 40 to move the first proximal articulation link 40 in the direction opposite to the movement of the second distal articulation link 42. The first proximal articulation link 40 is not coupled to the first distal articulation link 44. As such, when the first proximal articulation link 40 is moved in the direction of arrow “C” in FIG. 12A, the first distal articulation link 44 will remain stationary until the tool assembly 16 begins to articulate in the direction of arrow “A” in FIG. 13 . When the tool assembly 16 begins to articulate in the direction of arrow “A” (which occurs when the second distal articulation link 46 moves distally to pivot the tool assembly 16), the first distal articulation link 44 is pushed proximally by the pivot link 48. As such, when the tool assembly 16 is in an articulated position with the articulation lock assembly 80 in the unlocked position, the size of the space “S2” (FIG. 12A) between the first proximal articulation link 40 and the first distal articulation link 44 increases.

After the tool assembly 16 (FIG. 13 ) is articulated to a desired articulated position, e.g., 1 degree to 90 degrees, the direction of movement of the articulation drive member (not shown) is reversed to move the first and second proximal articulation links 40 and 42, respectively, in opposite directions independently of the first and second distal articulation links 44 and 46, respectively, to return the lock member 82 of the articulation lock assembly 80 to the locked position. More specifically, when the second proximal articulation link 42 moves in the direction of arrow “E” in FIG. 14 , the abutment member 58 a of the engagement member 58 of the second proximal articulation link 42 moves away from the distal ramped surface 98 a of the lock member 82 to allow the biasing member 84 to return the lock member 82 in the direction of arrow “F” to the locked position in which the protrusion 96 of the lock member 82 is received between adjacent teeth 74 a of the rack 74.

FIG. 15 illustrates operation of the articulation mechanism including the first and second articulation assemblies 38 and 39 as the tool assembly 16 is articulated to the other side of the stapling device 10 (FIG. 1 ). When the articulation drive member (not shown) of the adapter assembly 14 reverses movement of the first and second proximal articulation links 40 and 42, respectively, the second proximal articulation link 42 moves independently of the second distal articulation link 46 in the direction of arrow “F” to move the abutment member 58 a of the engagement member 58 within the cavity 60 defined in the proximal portion 46 a of the second distal articulation link 46 into engagement with the proximal ramp 98 b of the lock member 82. Engagement between the abutment member 58 a and the proximal ramp surface 98 b causes the lock member 82 to pivot in the direction indicated by arrow “G” from the locked position to the unlocked position. When the lock member 82 moves to the unlocked position, the distal abutment surface 45 a of the first proximal articulation link 40 which is moving in the direction of arrow “H” engages the proximal surface 44 c of the first distal articulation link 44 to move the first distal articulation link 44 in the direction of arrow “I” to pivot the tool assembly 16 (FIG. 1 ) to the other side of the stapling device 10 (FIG. 1 ). As the tool assembly 16 pivots, the second distal articulation link 46 which is coupled to the tool assembly 16 by the second pivot link 50 (FIG. 3 ) is driven proximally in the direction indicated by arrow “J”.

FIG. 16 illustrates the lock member 82 as the lock member 82 is moved back to the locked position. After the tool assembly 16 (FIG. 13 ) is articulated to a desired articulated position, e.g., 1 degree to 90 degrees, the direction of movement of the articulation drive member (not shown) of the adapter assembly 14 is reversed to move the first and second proximal articulation links 40 and 42, respectively, in opposite directions independently of the first and second distal articulation links 44 and 46, respectively, to return the lock member 82 of the articulation lock assembly 80 to the locked position. More specifically, when the second proximal articulation link 42 moves in the direction of arrow “K” in FIG. 14 , the abutment member 58 a of the engagement member 58 of the second proximal articulation link 42 moves away from the proximal ramped surface 98 b of the lock member 82 to allow the biasing member 84 to return the lock member 82 in the direction of arrow “L” to the locked position in which the protrusion 96 of the lock member 82 is received between adjacent teeth 74 a of the rack 74.

FIGS. 17-22 illustrate a cutaway view of the distal portion of the stapling device 10 (FIG. 1 ) with an alternate version of the articulation lock assembly shown generally as articulation lock assembly 180. Except for a minor modification to the second proximal articulation link 142 described below, all other aspects of the surgical stapling device 10 except for the articulation lock assembly 180 are the same as described above.

The articulation lock assembly 180 includes a lock member 182 and a biasing member 184 that urges the lock member 182 to the locked position (FIG. 19 ). In the articulation lock assembly 180, the lock member 182 includes distal and proximal ramp surfaces 198 a and 198 b and the distal portion 142 a of the second distal articulation link 142 includes an abutment member 58 that is received within a cavity 199 defined between the distal and proximal ramp surfaces 198 a and 198 b when the articulation lock assembly 180 is in the locked position. When the second proximal articulation link 142 is moved proximally or distally by the articulation drive member (not shown) of the adapter assembly 14 (FIG. 1 ), i.e., distally in the direction of arrow “M” in FIG. 21 or proximally in the direction of arrow “N” in FIG. 22 , the abutment member 58 engages one of the distal and proximal ramp surfaces 198 a and 198 b to move the lock member 182 in the direction of arrow “O” in FIGS. 21 and 22 from the locked position to the unlocked position.

In aspects of the disclosure, the lock member 182 is secured to the second distal articulation member 146 on a pivot member 190 that defines a horizontal axis as view in FIG. 17 that extends across the adapter assembly 14 and the lock member 182 includes a protrusion 196 that is received between adjacent teeth 174 a of a rack 174 as described above in regard to articulation lock assembly 80 when the lock member 182 is in the locked position. In the unlocked position of the lock member 182, the protrusion 196 is lifted from between the adjacent teeth 174 a of the rack 174 in the direction indicated by arrows “O” in FIG. 22 .

FIGS. 24-29 illustrate a cutaway view of the distal portion of the stapling device 10 (FIG. 1 ) with another alternate version of the articulation lock assembly shown generally as articulation lock assembly 280. Except for minor modification to the second proximal and distal articulation links 142 and 146 described below, all other aspects of the surgical stapling device 10 except for the articulation lock assembly 280 are the same as described above.

The articulation lock assembly 280 includes a lock member 282 and at least one biasing member 284. The lock member 282 includes a base member 286 that includes spaced guideposts 288 and a protrusion 290. The base member 286 has an outer surface 286 a that includes a distal ramp surface 282 a, a proximal ramp surface 282 b, and a raised central portion 282 c. The second distal articulation link 246 includes a proximal portion 246 a that defines two guide bores 292 that receive the guideposts 288 and a lock bore 294 that receives the protrusion 290. In aspects of the disclosure, the protrusion 290 extends through the lock bore 294 and into engagement with the rack 272 when the lock member 282 is in the locked position. The lock member 282 is supported on the proximal portion 246 a of the second distal articulation link 246 and movable linearly from a locked position in which the protrusion 290 is extended from the lock bore 294 and an unlocked position in which the protrusion 290 is withdrawn into the lock bore 294. In aspects of the disclosure, the biasing members 284 include a coil spring that is positioned about each of the guideposts 288 between the base member 286 of the lock member 282 and the proximal portion 246 a of the second distal articulation link 246 to urge the lock member 282 to the unlocked position (FIG. 29 ).

In some aspects of the disclosure, the second proximal articulation link 242 includes a cutout 296 and an abutment member 298 that extends across the cutout. When the lock member 282 in in the locked position, the abutment member 298 is engaged with the raised central portion 282 a of the lock member 282 to urge the lock member 282 to the locked position. In the locked position, the protrusion 290 extends through the lock bore 294 and into a position between adjacent teeth 274 a of the rack 274 to lock the second distal articulation link 246 from longitudinal movement. When the second proximal articulation link 242 is moved proximally or distally by the articulation drive member (not shown) of the adapter assembly 214, i.e., distally in the direction of arrow “P” in FIG. 28 or proximally in the direction of arrow “Q” in FIG. 29 , the abutment member 298 moves along one of the ramped surfaces 242 a and 242 b to allow the biasing member 284 to move the lock member 282 from the locked position (FIG. 27 ) to the unlocked position (FIG. 28 ) in the direction of arrows “R” in FIG. 28 .

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspects of the disclosure may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects of the disclosure. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A surgical stapling device comprising: an elongate body having a distal portion and a proximal portion and defining a longitudinal axis, the elongate body including a housing; a tool assembly pivotably secured to the distal portion of the elongate body about a pivot axis, the pivot axis being perpendicular to the longitudinal axis, the tool assembly movable between a non-articulated position and articulated positions; an articulation mechanism including a first articulation link assembly, the first articulation link assembly including a first proximal articulation link and a first distal articulation link, the first distal articulation link pivotably coupled to the tool assembly, the first proximal articulation link movable between retracted and advanced positions through a first intermediate position to move the first distal articulation link between retracted and advanced positions to move the tool assembly between a non-articulated position and articulated positions; a toothed rack having a plurality of teeth secured to the housing of the elongate body; and an articulation lock assembly including a lock member having a protrusion, the lock member secured to the first distal articulation link and movable between locked and unlocked positions in response to movement of the first proximal articulation link, the protrusion of the lock member received between adjacent teeth of the plurality of teeth of the toothed rack in the locked position of the lock member.
 2. The surgical stapling device of claim 1, wherein the lock member is pivotably supported on the first distal articulation link.
 3. The surgical stapling device of claim 2, wherein the articulation lock assembly includes a biasing member that urges the lock member towards the locked position.
 4. The surgical stapling device of claim 3, wherein the biasing member includes a coil spring.
 5. The surgical stapling device of claim 2, wherein the first distal articulation link defines a cavity and the lock member is pivotably supported within the cavity.
 6. The surgical stapling device of claim 5, wherein the first proximal articulation link has an engagement member that is received within the cavity and is movable into engagement with the lock member to move the lock member from the locked position to the unlocked position.
 7. The surgical stapling device of claim 6, wherein the lock member defines distal and proximal ramp surfaces and the engagement member includes an abutment member, the abutment member positioned between the distal and proximal ramp surfaces when the first proximal articulation link is in the first intermediate position and movable into engagement with one of the distal and proximal ramp surfaces to move the lock member from the locked position to the unlocked position.
 8. The surgical stapling device of claim 6, wherein the engagement member of the first proximal articulation link is coupled to the first distal articulation link to facilitate movement of the first proximal articulation link independently of the first distal articulation link as the lock member is moved between the locked position and the unlocked position.
 9. The surgical stapling device of claim 1, wherein the first articulation link assembly includes a first pivot link, the first pivot link having a proximal portion that is pivotably coupled to the first distal articulation link and a distal portion that is pivotably coupled to one side of the tool assembly.
 10. The surgical stapling device of claim 1, wherein the articulation mechanism further includes a second articulation link assembly, the second articulation link assembly including a second proximal articulation link, a second distal articulation link, and a second pivot link, the second proximal articulation link movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link and the second pivot link between retracted and advanced positions.
 11. The surgical stapling device of claim 10, wherein the second proximal articulation link is coupled to the second distal articulation link to facilitate independent movement of the second proximal articulation link in relation to the second distal articulation link as the lock member moves between the locked and unlocked positions.
 12. An articulation mechanism comprising: a first articulation link assembly including a first proximal articulation link and a first distal articulation link, the first proximal articulation link movable between retracted and advanced positions through a first intermediate position to move the first distal articulation link between retracted and advanced positions; and an articulation lock assembly including a toothed rack having a plurality of teeth and a lock member having a protrusion, the lock member secured to the first distal articulation link and movable between locked and unlocked positions in response to movement of the first proximal articulation link, wherein the first proximal articulation link is coupled to the first distal articulation link to facilitate relative movement between the first proximal articulation link and the first distal articulation link as the lock member is moved between the locked and unlocked positions, the protrusion of the lock member received between adjacent teeth of the plurality of teeth of the toothed rack in the locked position of the lock member.
 13. The articulation mechanism of claim 12, further including a second articulation link assembly including a second proximal articulation link and a second distal articulation link, the second proximal articulation link movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link between retracted and advanced positions, the second proximal articulation link coupled to the second distal articulation link to facilitate relative movement between the second proximal articulation link and the second distal articulation link as the lock member is moved between the locked and unlocked positions.
 14. The articulation mechanism of claim 13, wherein the lock member is pivotably supported on the first distal articulation link and is urged to the locked position by a biasing member.
 15. The articulation mechanism of claim 14, wherein the biasing member includes a coil spring.
 16. The articulation mechanism of claim 12, wherein the first distal articulation link defines a cavity and the lock member is pivotably supported within the cavity.
 17. An articulation mechanism comprising: a first articulation link assembly including a first proximal articulation link and a first distal articulation link, the first proximal articulation link movable between retracted and advanced positions through a first intermediate position to move the first distal articulation link between retracted and advanced positions, the first distal articulation link defining a cavity and the lock member is pivotably supported within the cavity; and an articulation lock assembly including a lock member, the lock member secured to the first distal articulation link and movable between locked and unlocked positions in response to movement of the first proximal articulation link, wherein the first proximal articulation link is coupled to the first distal articulation link to facilitate relative movement between the first proximal articulation link and the first distal articulation link as the lock member is moved between the locked and unlocked positions; wherein the first proximal articulation link has an engagement member that is received within the cavity and is movable into engagement with the lock member to move the lock member from the locked position to the unlocked position.
 18. The articulation mechanism of claim 17, wherein the lock member defines distal and proximal ramp surfaces and the engagement member includes an abutment member, the abutment member positioned between the distal and proximal ramp surfaces when the first proximal articulation link is in the first intermediate position and movable into engagement with one of the distal and proximal ramp surfaces to move the lock member from the locked position to the unlocked position.
 19. A surgical stapling device comprising: an elongate body having a distal portion and a proximal portion and defining a longitudinal axis, the elongate body including a housing; a tool assembly pivotably secured to the distal portion of the elongate body about a pivot axis, the pivot axis being perpendicular to the longitudinal axis, the tool assembly movable between a non-articulated position and articulated positions; an articulation mechanism including first and second articulation link assemblies, the first articulation link assembly including a first proximal articulation link and a first distal articulation link, the first distal articulation link pivotably coupled to the tool assembly, the first proximal articulation link movable between retracted and advanced positions through a first intermediate position to move the tool assembly between a non-articulated position and articulated positions, the second articulation link assembly including a second proximal articulation link and a second distal articulation link, the second proximal articulation link movable between retracted and advanced positions through a second intermediate position to move the second distal articulation link and the second pivot link between retracted and advanced positions to move the tool assembly between the non-articulated and articulated positions; a toothed rack having a plurality of teeth secured to the housing of the elongate body; and an articulation lock assembly including a lock member having a protrusion and a biasing member, the lock member secured to the first distal articulation link and movable between locked and unlocked positions in response to movement of the first proximal articulation link the protrusion of the lock member received between adjacent teeth of the plurality of teeth of the toothed rack in the locked position of the lock member, the biasing member positioned to urge the lock member towards the locked position. 